So, you need a new pair of shades. You could take the scattershot approach and try on every pair you can get your hands to test out what looks good... or you could play it smart and break down the types that'll work for you so that you know what to look for.

The first step is determining your face shape. There's no exact science to this, but they mostly have to do with how your jawline slopes down your face, so that's the area you want to focus on. There are three basic types:

• Rounded – Think Daniel Craig. His jawline slopes gently from his ears to his chin, creating an oval shape.

• Squared – Think David Beckham. His jawline is a lot lower and squared off, so his face looks a little more blocky.

• Heart-Shaped – Think Tom Hiddleston. His jaw and chin slope down into a more pointed shape, which makes for a more angular effect.

Once you've got that down, you need to pair your sunglass' shape to your face's. There are two basic schools of thought here: you either match or contrast. For example, a square faced guy could match his face with a square pair of sunglasses, or contrast with a circular pair. We think that matching works much better, so:

Rounded Face? Rounded Frames.

If you've got a gently sloped jawline, complement the rounder profile with frames like aviators or any other design that has soft edges. That way, the frames mold more closely to your face rather than sharply contrasting with your natural profile.

Squared Face? Squared Frames.

The same principle applies here: you want to mirror your natural face shape with your sunglasses' so that they frame you in a smooth, complementary way. And when you've got a sharp, squared-off jawline, that means reaching for more angular shades like Wayfarers or other rectangular designs.

Heart-Shaped Face? Whatever You Want.

These guys are the lucky ones who get to wear pretty much anything. Aviators will look especially good because of their similar teardrop shape, which follows the matching rule. But but you can get away with any other style, from boxy square shades to smaller circular ones, too.